Book Closing in HEAD kills objects in a "bad" order, corrupts memory.

[Derek Atkins]

linas at linas.org (Linas Vepstas) writes:

> Hey' didn't you write that code? I think its pulling from a hash table,
> which is why its random order.  I don't remember how things work during
> startup.  It should be easier during startup, where one can clearly
> spec a dependency graph (this depends on that being intited, so go init
> that now).

Yes, I wrote this code...  but when I did write it the only users were
the business functions.  The existing engine objects had a
well-defined load/unload order, but I implemented the business objects
to handle loading and unloading in random order.  For example, if an
Invoice gets loaded before it's Customer, it'll create a Customer
Placeholder object -- so when the Customer gets loaded it will fill in
the placeholder.  Voila, random loading.

The only potential problem is if you have dangling references, but
that can only happen with a corrupted data file.  The program enforces
the references.

This is also why I never implemented "delete"  :)

-derek

-- 
       Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
       Member, MIT Student Information Processing Board  (SIPB)
       URL: http://web.mit.edu/warlord/    PP-ASEL-IA     N1NWH
       warlord at MIT.EDU                        PGP key available